System of selective control.



J. HAMMOND, JR. SYSTEM OF SELECTIVE CONTROL,

APPLICATION FILED SEPT. 7,1911.

Patented June 2, 1914.

2 SHEETS-SHEET l.

I. H. HAMMON D, JR. SYSTEM OF SELECTIVE CONTROL.

APPLICATION FILED SEPT. 7, I 1,098,379. w Patented June 2, 1914 2 SHEETS-SHEET 2.

UNITED STATES PATENT ormoE.

JOHN HAYS HAMMOND, JR., OF GLOUCESTER, MASSACHUSETTS.

: tivelyby the receiving station.

' -The principal objectof the invention is to produce a system whereby the opening or closing of a local circuit may be controlled without liability to interference.

The various other objects of the invention will be more fully set forth in the following description of one form of apparatus suitable for practising the invention.

In the particular apparatus.shown in the accompanyin drawings for the purpose of illustrating t e operation of my improved system, waves of light, having a plurality of fluctuations impressed thereon by a micro- .phone, are emitted from the sending station and received by the selenium cell at the receiving station, but it will be obvious that any suitable means of propagatin ether disturbances may be employed whic will per- -mined frequencies. .In the drawings,

mit a plurality of fluctuations of predeter Figure 1 is a diagrammatic view of one form of apparatus for carrying out my improved system, Fig. 2 is a corresponding view showing different connections in the receiving station.

In the particular apparatus shown in the drawings for the purpose of illustratin my improved system, a motor 1 drives a irect current generator 2 which feeds an arc-lamp 8. In the arc lamp circuit are included resistance 4 and self-inductance 5 to steady the arc. The secondary 6 of a transformer is also included in this circuit, the primary of which transformer 7 istraversed by currents emanating from battery 8 and controlled by microphone 9. The microphone is acted upon by vibrations from'a number of reeds 10, 11 and 12, which have their individual and fixed vibrating frequencies.

When the reeds are vibrated-by means of any convenient method, they emit-a chord of three definite frequencies, which are reproduced by means of-a microphone and varia--.

Specification of Letters Patent. Application filed September 7, 1911 .Serial No. 648,225.

SYSTEM OF SELECTIVE CONTROL.

Patented June 2,1914.

tions of the microphone current. The transformer, whose primary is 7 and secondary 6,- therefore produces alternating potentials at secondary 6 which produces 1n the are circuit alternating currents of the three frequencies superimposed on the direct currents furnished by generator 2. The light emitted from the are 3 has periodic increases and decreases governed by the alternating cur rents in the arc circuit.

A reflector 14 is arranged at the receiving station and is focused so as to concentrate apart of the light from the are upon a selemum cell 15 in circuit 16 with a battery 17 through circuit 16 which fluctuates very much the same as thexconductivity of the selenium cell 15, the currents of'circuit 16 belng therefore of direct current with superimposed currents of .the' three frequencies.

In circuit 16 are also included the three.

25 and 26, are mounted in proximity to the coils 18, 19 and 20; reed 24 having the same perlod of vibrationasreed 10 of the transmitter; reed 25 havin the sameperiod of vibration as reed 11 o the transmitter; and

reed 26 having the same period of vibration as reed 12 of the transmitter. Consequently, when the transmitter reeds 10, 11 and 12 are caused to vibrate, the receiving reeds 24,25 and 26 will also be caused to vibrate and will attain an appreciable amplitude by virtue of resonance. Suitable means 27, 28 and 29 are arranged in circuit'with polarized relays 30,

31' and 32 whereby appreciable vibrations of.

"and 41 will close local circuits 42, 43 and 44 having batteries 45, 46 and 47 respectively which energize magnet coils 48, 49 and 50 respectively. Said magnet. coils in turn attract armatures 51, 52 and 53 thus completing the local circuit 54 comprising a battery 55 which energizes the magnet CO1 56. Said 'coil ther. draws armature 57 to contact 58 whereby any suitable means as the batter 59 is made to energize a plunger magnet coil or solenoid 60, which in turn actuates plunger and thus controls any desired form of operative mechanism, such as a lever 72 Battery 17 will therefore send a current coils 18, 19 and 20, of the three vibratory relays 21, 22 and 23. The tuned reeds 24,

loo

I action of the three 55- cies of fluctuation.

connected with the plunger by any suitable connection as the chain 71.

In the modified form of apparatus shown for the purpose of illustration in.Fig. 2, the sending station is represented as being iden tical to the sending station shown in Fig. 1 and the receiving station is provided with a selenium cell in circuit 16 comprising the battery 17. In this construction, how- 10 ever, the corresponding coils 18, 19 and 20' are in multiple withthe circuit 16. Coils 19 and 20, however, do not connect directly to the line wires 16 and 16? of the circuit 16 but depend for their final connection on the 5 closing of armatures 51 and52 with the contact points 7 3 and 74'. In this construction, variations of the conductivity of the selenium cell 15 causes battery 17 to send fluctuating currents to the coil 18 which 0 through reed 24: and controlling means 27 actuates the polarized relay 30 and by means of relay coil 48 attracts armature 51 to a point 73. Coil 19 is thereupon ener-- gized thereby energizing the vibratory reed 25 which, by the controlling, means 28,

operates a polarized relay 31 thus closing circuit 43 and energizing relay coil 4:9, the armature 52 of which connects coil 20 to the line wires 16 and 16". Said coil 20' l causes reed 26 to vibrate and through controlling means 291 operates the polarized relay 32, the armature 38' of which is connected to a point 41 thus closing the circuit 44 comprising the battery 47 which operates relay coil 50'. .The armature 53 of said coil 50' then closes the local circ it 54, including the battery 55, in which the relay coil 56 is located. The armature 57 of this relay makes contact with point 58' thus permitting the battery 59' to energize plunger coil of solenoid 60, the plunger 61' of which is operatively connected by any suitable means as the chain 62 to the lever 63.

In the construction shown in the drawings conjoint action of the transmitter reeds 10,

11 and 12 is required to complete circuit 54:, or circuit 54, respectively. J

In the construction particularly shown in Fig. 1, reed relays are arranged in series,

whereas in Fig. 2, they are arranged in multiple, but in both cases conjoint action is re-' quired, thus rendering the system proof against interference except by the combined predetermined frequen- Itwill be obvious, of course. that various other means of producing the three predetermined frequencies may be employed, since 1 I it is well known'that they can-be produced through sending station comprising various means for emitting either dampened or un- 7 Q dampened vibrations, and it will be .understood that' in illustrating the invention in connection with an apparatus employing 65 lightwaves, I have merelyv shown a preferred form of apparatus embodying my improved system.

I claim-as myinvention: 1. In a system of the character described, a receiving station adapted to receive light vibrations whose characteristics are such as to produce fluctuations of predetermined frequencies in the receiving station, said receiving station comprising means to respond to each of said fluctuations of different frequency and said means operating conjointly to close a local clrcuit.

2. In a system of the character described,

a receiving station adapted to receive light vibrations having a plurality of fluctuations of predetermined frequencies, means for causing these fluctuations of predetermined frequency to produce appreciable vibrations of a plurality of receiving means, and means for controlling a local circuit through such brations having a plurality of fluctuations ofpredetermined frequencies, means for causing the fluctuations of each frequency to produce appreciable vibrations of separate'receiving means, and means for controlling a local circuit through the conjoint action of such receiving means.

5. Ina system of the character described,

a receiving station adapted to receive ether vibrations having a plurality of fluctuations Tof predetermined frequencies, means for each frequency toproduce appreciable vibrations of separate causing fluctuations o monotone vibratingrelays, said relays being in. parallel circuits and means for controlling-a local circuit by the action of such rela s.

In a system of the .characterdescribed, a receiving stat-ion adapted to receive ether vibrations having a plurality of fluctuations of predeterminedfrequencies, and comprising a plurality of monotone vibrating relays, said relays being arranged in parallel circuits, means for causing the fluctuations of each predetermined frequency to produce .mechanical vibration of one of said relays,

and means for controlling an independentlo'cal circuit through the conjoint action of said relays. I 7. Ina system of the character described, a sending station comprising an'arc, means for simultaneously impressing variations of a plurality of predetermined rates upon the ether vibrations produced said arc, a receivlng circuit com rismg a selenium cell to receive said ether vi rations having said predetermined variations impressed thereon, means for causmg said variatlons to produce mechanical vibrations in a plurality of tuned predetermined acoustic tone whereby a pluralityof fluctuations of predetermined frequency are impressed on said ether vibrations, a receiving'station comprising a selen- 1111;)? cell to receive said vibrations, and a plum1 y of monotone vibrating relays each re- -ve to the fluctuations produced by one Ufa-Said pipes, and-"means for controlling a locai circuit through such relays.

' 9. In a system of the character described,-

a sending station comprising an arc producing ether vibrations, a microphone inductively coupled with said are, and a plurality of acoustic pipes each capable of emitting a predetermined acoustic tone whereby'a plurality of fluctuations of predetermined frequency are impressed on said ether vibrations, a receiving station comprising a selenium cell to receive said vibrations, a plural-' ity of separate monotone vibrating relays each responsive to the fluctuations produced by one of said pipes and arranged in circuit with each other, a plurality of polarized relays in circuit with said vibrating relays, and an independent local circuit controlled by the conjoint action of said polarized relays.

This specification slgned and witnessed this lst'day-of September, A. D., 1911.

JOHN HAYS HAMMOND, JR.

Witnesses:

Z..F. PHELPS, AMBROSE L. OSHEA. 

